Services' home lists every programmable service: live, an API reference and a grantable capability (AI, Events and Search have no site block; their product taglines describe them) (#7)

ddiff --git a/server/http/pages.js b/server/http/pages.js
iindex 0470baf..5d8adfa 100644
---- a/server/http/pages.js
++++ b/server/http/pages.js
@@@ -62,13 +62,15 @@ const ov = createClient({
      }),
  });
  const services = await ov.registry.services();`;
--        // The services a project can call: every live service whose manifest lists a capability an app can be
--        // granted, linked to its generated API reference. Read from the pinned contracts, never typed here.
++        // The services a project can call: every live service with a generated API reference and at least one
++        // capability an app can be granted (Services itself aside), with its tagline from its site block or its
++        // product manifest. Read from the pinned contracts, never typed here.
          const apiDocs = new Set(contracts.openapi.index().map((x) => x.service));
++        const productTagline = new Map(contracts.products.catalog().filter((p) => p.relationships && p.relationships.service && p.tagline).map((p) => [p.relationships.service, p.tagline]));
++        const grantable = (m) => (m.capabilities || []).some((c) => { const cap = contracts.capabilities.get(c); return cap && cap.status === 'active' && cap.visibility === 'public'; });
          const programmable = contracts.services.manifests
--            .filter((m) => m && m.site && m.exposure && m.exposure.state === 'live' && m.exposure.publicSite === 'service')
--            .filter((m) => (m.capabilities || []).some((c) => { const cap = contracts.capabilities.get(c); return cap && cap.status === 'active' && cap.visibility === 'public'; }))
--            .sort((a, b) => (a.site.position ?? 99) - (b.site.position ?? 99));
++            .filter((m) => m && m.id !== 'services' && m.exposure && m.exposure.state === 'live' && apiDocs.has(m.id) && grantable(m))
++            .sort((a, b) => ((a.site && a.site.position) ?? 50) - ((b.site && b.site.position) ?? 50) || a.name.localeCompare(b.name));
          page(req, res, {
              index: true, cache: PUBLIC_CACHE,
              jsonLd: homeJsonLd(config),
@@@ -97,8 +99,8 @@ ${programmable.length ? raw(showcase.features({
                  id: 'services', title: 'Services you can build on', lede: 'Each one runs in production today; its API reference is generated from the capabilities it declares.',
                  // Text only: an inline icon per service would double the page's weight (the home page's budget).
                  items: programmable.map((m) => ({
--                    title: m.name, text: m.site.tagline || '',
--                    href: apiDocs.has(m.id) ? `/docs/api/${m.id}` : m.publicOrigin,
++                    title: m.name, text: (m.site && m.site.tagline) || productTagline.get(m.id) || '',
++                    href: `/docs/api/${m.id}`,
                  })),
              })) : ''}
  ${raw(showcase.steps({